The effect of early arm exercise on drainage volume after total mastectomy and tissue expander insertion in breast cancer patients: a prospective study

Background In prosthesis-based breast reconstruction patients, the drain tends to be kept in place longer than in patients who undergo only mastectomy. Postoperative arm exercise also increases the drainage volume. However, to preserve shoulder function, early exercise is recommended. In this study, we investigated the effect of early exercise on the total drainage volume and drain duration in these patients.Methods We designed a prospective randomized trial involving 56 patients who underwent immediate breast reconstruction following mastectomy using tissue expanders. In each group, the patients were randomized either to perform early arm exercises using specific shoulder movement guidelines 2 days after surgery or to restrict arm movement above the shoulder height until drain removal. The drain duration and the total amount of drainage were the primary endpoints.Results There were no significant differences in age, height, weight, body mass index, or mastectomy specimen weight between the two groups. The total amount of drainage was 1,497 mL in the early exercise group and 1,336 mL in the exercise restriction group. The duration until complete removal of the drains was 19.71 days in the early exercise group and 17.11 days in the exercise restriction group.Conclusions Exercise restriction after breast reconstruction did not lead to a significant difference in the drainage volume or the average time until drain removal. Thus, early exercise is recommended for improved shoulder mobility postoperatively. More long-term studies are needed to determine the effect of early exercise on shoulder mobility in prosthesis-based breast reconstruction patients.

Differences in Glucose Readings Between Right Arm and Left Arm Using a Continuous Glucose Monitor

Objective: Continuous glucose monitoring (CGM) devices are used for evaluating real-time glucose levels to optimize diabetes management. There is limited information, however, on whether readings differ when a device is placed on the right versus the left arm. This study evaluated the mean difference in glucose levels between the right and left arm and the effect of unilateral arm exercise on this difference. The effect of an intermittent fasting diet on body fat percentage was also evaluated. Research Design and Methods: In a prospective trial, 46 adult volunteers self-selected into the intermittent fasting (IF; N = 23) or free-living (FL; N = 23) diet group and were randomized into a unilateral arm exercise group. Volunteers had CGM sensors placed simultaneously on both arms for 12-14 days. Results: The mean glucose level in the right arm was significantly higher than the left arm by 3.7 mg/dL ( P < .001), and this result was unaffected by diet or arm exercise. Glucose levels were in euglycemic range for 75.2% of the time in the right arm and 67.5% in the left arm ( P < .001). The change from baseline in body fat percentage between the IF and FL diet groups was not significant. Conclusions: Measured glucose level and time in euglycemic range differ per placement of the CGM device, and the implications of this difference should be considered in clinical practice and research.

Abstract 13259: Differences in Glucose Readings Between Right Arm and Left Arm Using a Continuous Glucose Monitor

Introduction: Poorly controlled diabetes increases the risk of cardiovascular disease and associated complications. Continuous glucose monitoring (CGM) devices are tools that allow clinicians and patients to gather real-time glucose levels to enhance glycemic control. CGM devices are increasingly used to optimize diabetes management, but there is no guidance on whether glucose readings differ when a CGM device is placed on the right versus the left arm. We assessed the hypothesis that a difference in time-matched glucose levels will be observed between the right and left arm. Methods: This prospective trial enrolled 46 adult volunteers to simultaneously wear CGM sensors on the right and left arms. Glucose readings were collected every 15 minutes over a 12-14 days study period. To assess if any observed inter-arm differences were a result of perfusion, participants were randomized to perform a daily 20-minute unilateral arm exercise using an assigned arm on Days 1-6, and to use the alternate arm from Day 7 to Days 12-14. Differences in glucose readings between the right and left arm were compared using the paired sample t-test. Results: A total of 41,288 time-matched glucose level pairs were collected and the mean glucose reading in the right arm was higher than that of the left arm by 3.7±10.6 mg/dL (p<0.001). Glucose readings were in hypoglycemic range (<70 mg/dL) for 22.1% of the time in the right arm and 29.8% of the time in the left arm (p<0.001), in euglycemic range (70-180 mg/dL) for 75.2% of the time in the right arm and 67.5% in the left arm (p<0.001), and in hyperglycemic range (>180 mg/dL) for 2.8% of the time in both arms (p=0.83). The difference in glucose levels between the arms was similar before and during exercise [4.0±10.2 mg/dL vs. 4.3±10.1 mg/dL, p=0.77]. Conclusions: In conclusion, glucose levels and time in hypoglycemia and euglycemia significantly differ based on arm selection during CGM device placement. This finding is unrelated to differences in perfusion induced by unilateral arm exercise. If these findings are further validated in patients with diabetes, arm selection during CGM device placement could impact therapy decisions, clinical trial design, and interpretation.